A blooming amaryllis can add sparkle to holiday decorations and cheer during the short days and long nights of winter.
The amaryllis, in the genus Hippeastrum, is a large bulb that produces 4 to 10-inch trumpet-shaped flowers ranging in colors from red, white, pink, and salmon on a 1 to 2-foot stalk. This bulb, native to Central and South America, derives its name from a Greek word that means “to sparkle.”
Around the holiday season, you will find them for purchase at grocery and hardware stores as well as garden centers. They are sold as dormant bulbs, as pre-potted bulbs, or in kits with potting soil.
When choosing amaryllis bulbs, select healthy ones. These will be firm and dry with no shriveling, decay, mold, or signs of injury. When planting or repotting, which is recommended every three to four years, choose a pot with good drainage. It should be 1 inch wider than the widest part of the bulb and twice as tall. A slightly pot-bound bulb will bloom better. Fill the pot half full with new sterile potting mix high in organic matter. Place the bulb in the soil so that the top of the bulb sits slightly above the edge of the pot. Add more soil around the bulb, allowing 1/3 to 1/2 of the bulb to remain visible. Keep the top portion of the bulb uncovered to help prevent fungal disease. Water thoroughly when planting and when the soil feels dry to the touch, about once a week. Place it in a sunny window and rotate the pot occasionally to prevent the plant from leaning as it grows.
Once flower buds begin to open, move the pot out of direct sunlight and away from heat sources to prolong flowering. After the flowers fade, cut them off to prevent seed formation, which depletes energy reserves in the bulb and can reduce future blooming. Flower stalks may be removed once they turn yellow, but do not remove the green leaves. After it is done blooming, it can be placed again in a sunny indoor location that receives a minimum of four hours of daily sunlight. A south-facing window is ideal for optimizing photosynthesis. This is also the time to begin fertilizing. To promote blooming, use a water-soluble houseplant fertilizer twice a month. When the weather warms, and the danger of frost is passed, it can be brought outside. Slowly introduce your amaryllis to the harsher outside environment so it may become acclimated to the changes in sunlight and temperature. Be sure to bring them inside before frost as they are a tender bulb and not winter hardy in Pennsylvania.
Amaryllis bulbs do not require a dormancy period to rebloom. However, to encourage them to rebloom around holiday time, initiate a dormancy period in late summer to early fall. To do this, move the plant into a cool (50°F to 60°F), dry, and dark location for eight to twelve weeks. During this time, withhold water and fertilizer. The leaves will wither and can be removed. When new growth starts to emerge at the top of the flower bulb, trim away any dead leaves, move to a sunny location, and begin watering. Even if you do not see new growth after eight to twelve weeks, move into the sun and resume watering. Remember to rotate the pot to prevent the plant from leaning as it grows. The leafless flower stalks will emerge, and you should expect to see flowers in about four to six weeks.
A healthy bulb will produce young bulbs, or offsets, at its base of the bulb where the roots originate. These offsets may be allowed to continue to grow with the mother bulb to produce a larger display of blooms. Alternatively, the offsets can be removed to create new plants. After a dormant period and when the offsets are ¼ to ⅓ the size of the mother bulb, detach the offsets and plant as you would a new bulb. Be patient. The new bulbs will require a few years to reach a size large enough to flower.
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